With the potential for winter storms to bring down trees and cover the pond in thick layers of ice, it’s tempting to cover the entire pond in a tarp or cover for protection. Yet, this impulse can backfire and harm the pond and its residents; especially if the pond is small or the cover is solid. Other forms of more permeable cover that let water and air flow through in both directions are actually useful and may even be required in some areas. Find out what kind of cover you should and shouldn’t use on a pond over the winter, specifically if there are fish and plants in the water.
Solid Covers for Snow and Ice
Many new pond owners are surprised that it’s so uncommon to cover a pond with a solid tarp or cover in the winter. However, this traps gases that normally evaporate from the surface of the water, even in winter. A tarp or solid cover, that doesn’t let air move through, is just as bad as a solid layer of ice capping the water. Any fish or plants under the surface will suffer and eventually die off from the build-up of gases. Solid covers can be used for short periods or if they’re suspended above the surface enough to let air circulate underneath the material. Don’t forget to consider the weight of accumulated snow and rainfall on the surface of the cover when securing it to the edges of the pond.
Nets and Permeable Covers
On the opposite end of the cover spectrum, permeable covers like nets and open weave tarps can work well for winter protection. In fact, they’re often recommended for predator control where fish are prone to being eaten over the winter. The key is that the cover is open enough to allow both rain and snow to fall into the pond and for air to rise off the surface. Suspending this kind of cover over the surface of a large pond is challenging, but it’s worth the effort for a fishpond. Winter covers can make the difference between a healthy fish stock in the spring or a pond that is practically empty.
Ice Cover
One type of cover that is particularly damaging to fish, but fine for other types of ponds, is ice. A complete cover of ice is acceptable on a pond with no fish since there’s no damage to the liner or banks from gas build-up. Fish won’t like being trapped under a solid layer of ice since it leaves them struggling to get enough oxygen. De-icing, to leave holes in the ice, is recommended for fish ponds but is relatively unnecessary for most other types of ponds.
As long as the pond is designed correctly from the start, a cover shouldn’t be necessary for more than temporary storm or snow protection. If you need a durable and reliable pond cover for short-term winter use, consider one of the many products available from BTL Liners.
